Apparatus for spreading open flat bags
AssigneeSIG Schweizerische Industrie-Gesellschaft
InventorWerner Muller
Life of this patent
Estimating the term…
Abstract
An apparatus for spreading open flattened bags has a first air-pervious endless belt having a working flight provided with a working face and an opposite, reverse face; and a second air-pervious endless belt having a working flight provided with a working face and an opposite, reverse face. The working flights of the first and second belts are divergent at an acute angle in the bag conveying direction. There is further provided a suction device generating a vacuum for urging a gas to flow across the working flights in a direction from the working face to the reverse face of each working flight, whereby each bag introduced between the working flights adheres, with opposite bag panels, to the working faces of the working flights and is forwarded thereby in the conveying direction, while being gradually spread open.
Claims16
An apparatus for spreading open flattened bags having an open side while the bags are advanced in a conveying direction, comprising
- (a) a first air-pervious endless belt having a working flight provided with a working face and an opposite, reverse face;
- (b) first end rollers supporting the first belt;
- (c) a second air-pervious endless belt having a working flight provided with a working face and an opposite, reverse face;
- said working flights of the first and second belts being oriented towards one another and being divergent at an acute angle in the conveying direction;
- (d) second end rollers supporting said second belt;
- (e) means for driving said first and second belts for effecting a travel of the working flights thereof in the conveying direction;
- (f) feeding means for sequentially advancing the bags to a common upstream end of the first and second belts, as viewed in the conveying direction;
- (g) suction means for generating a vacuum for urging a gas to flow across the working flights in a direction from the working face to the reverse face of each working flight, whereby each bag introduced by said feeding means between the working flights at said upstream end adheres, with opposite bag panels, to the working faces of the working flights and is forwarded thereby in the conveying direction, while being gradually spread open;
- (h) a third air-pervious endless belt having a working flight provided with a working face and an opposite, reverse face;
- said working flight of said third belt adjoining the working flight of said first endless belt in a flush, parallel relationship therewith;
- said working flight of said third belt extending from said upstream end beyond a downstream end of said first belt;
- (i) third end rollers supporting said third belt;
- (j) a fourth air-pervious endless belt having a working flight provided with a working face and an opposite, reverse face;
- said working flight of said fourth belt adjoining the working flight of said second belt in a flush, parallel relationship therewith;
- said working flight of said fourth belt extending from said upstream end beyond a downstream end of said second belt;
- said working flights of said third and fourth belts being oriented towards one another;
- (k) fourth end rollers supporting said fourth belt;
- and
- (l) additional suction means for generating a vacuum for urging a gas to flow across the working flights of said third and fourth belts in a direction from the working face to the reverse face of the working flight of the third and fourth belts.
An apparatus for spreading open flattened bags having an open side while the bags are advanced in a conveying direction, comprising
- (a) a first air-pervious endless belt having a working flight provided with a working face and an opposite, reverse face;
- (b) first end rollers supporting the first belt;
- (c) a second air-pervious endless belt having a working flight provided with a working face and an opposite, reverse face;
- said working flights of the first and second belts being oriented towards one another and being divergent at an acute angle in the conveying direction;
- (d) second end rollers supporting said second belt;
- (e) means for driving said first and second belts for effecting a travel of the working flights thereof in the conveying direction;
- (f) feeding means for sequentially advancing the bags to a common upstream end of the first and second belts, as viewed in the conveying direction;
- (g) suction means for generating a vacuum for urging a gas to flow across the working flights in a direction from the working face to the reverse face of each working flight, whereby each bag introduced by said feeding means between the working flights at said upstream end adheres, with opposite bag panels, to the working faces of the working flights and is forwarded thereby in the conveying direction, while being gradually spread open;
- and
- (h) means for shifting said first and second belts as a unit in a direction perpendicular to the conveying direction.
Dependencies are inferred from the claim text.